wasmtime / issue #8955 Overriding `argv[0]` for `wasmtime... · git-wasmtime

Stream: git-wasmtime

Topic: wasmtime / issue #8955 Overriding `argv[0]` for `wasmtime...

Wasmtime GitHub notifications bot (Jul 14 2024 at 13:52):

whitequark opened issue #8955:

Feature

I would like it to be possible to override argv[0] for commands executed with wasmtime run. E.g.:
wasmtime run --argv0=clang++ bin/clang.wasm ...
Benefit

Certain applications use the value of argv[0] to:

Dispatch between incompatible code paths (multi-call binaries), e.g. Clang;

Discover location of data via executable-relative paths, e.g. also Clang in some cases.

In general I think the path passed to wasmtime run is only meaningful on the host and will rarely if ever mean anything within the sandbox.

Implementation

A new option --argv0= would work for me, but really anything that gets the job done is fine.

Alternatives

I can't think of any besides not having the functionality.

Wasmtime GitHub notifications bot (Jul 14 2024 at 13:52):

whitequark edited issue #8955:

Feature

I would like it to be possible to override argv[0] for commands executed with wasmtime run. E.g.:
wasmtime run --argv0=clang++ bin/clang.wasm ...
Benefit

Certain applications use the value of argv[0] to:

Dispatch between incompatible code paths (multi-call binaries), e.g. Clang;

Discover location of data via executable-relative paths, e.g. also Clang in some cases (not the usual configuration though).

In general I think the path passed to wasmtime run is only meaningful on the host and will rarely if ever mean anything within the sandbox.

Implementation

A new option --argv0= would work for me, but really anything that gets the job done is fine.

Alternatives

I can't think of any besides not having the functionality.

Wasmtime GitHub notifications bot (Jul 15 2024 at 14:22):

alexcrichton commented on issue #8955:

This sounds reasonable to me to implement as well, and I think --argv0 is a fine name as well. We already infer it from the provided wasm module so providing the ability to customize that seems like a good idea.

Wasmtime GitHub notifications bot (Jul 15 2024 at 14:29):

whitequark commented on issue #8955:

I was going to implement it originally, but unfortunately I lost the direct motivation for this as I've moved to shipping the combined LLVM compiler driver (the llvm command, if you've seen it, as it's a bit obscure... it's like busybox) which takes the command to invoke as argv[1].

Wasmtime GitHub notifications bot (Jul 15 2024 at 14:29):

whitequark edited a comment on issue #8955:

I was going to implement it originally, but unfortunately I lost the direct motivation for this as I've moved to shipping the combined LLVM compiler driver (the llvm command, if you've seen it, as it's a bit obscure... it's like busybox) which takes the command to invoke as argv[1]. The combined binary is about 25% smaller so it's clearly preferable to ship.

Wasmtime GitHub notifications bot (Jul 15 2024 at 14:30):

whitequark edited a comment on issue #8955:

I was going to implement it originally, but unfortunately I lost the direct motivation for this as I've moved to shipping the combined LLVM compiler driver (the llvm command, if you've seen it, as it's a bit obscure... it's like busybox with every single tool compiled into it) which takes the command to invoke as argv[1]. The combined binary is about 25% smaller so it's clearly preferable to ship.

Wasmtime GitHub notifications bot (Jul 15 2024 at 21:57):

alexcrichton closed issue #8955:

Feature

I would like it to be possible to override argv[0] for commands executed with wasmtime run. E.g.:
wasmtime run --argv0=clang++ bin/clang.wasm ...
Benefit

Certain applications use the value of argv[0] to:

Dispatch between incompatible code paths (multi-call binaries), e.g. Clang;

Discover location of data via executable-relative paths, e.g. also Clang in some cases (not the usual configuration though).

In general I think the path passed to wasmtime run is only meaningful on the host and will rarely if ever mean anything within the sandbox.

Implementation

A new option --argv0= would work for me, but really anything that gets the job done is fine.

Alternatives

I can't think of any besides not having the functionality.

Wasmtime GitHub notifications bot (Jul 15 2024 at 23:47):

whitequark commented on issue #8955:

Thank you!

Last updated: Dec 23 2024 at 12:05 UTC